The present disclosure is related to systems and methods for dental appliance compliance indication.
As noted in commonly owned U.S. Pat. No. 6,607,382 entitled “Methods and systems for concurrent tooth repositioning and substance delivery,” the content of which is incorporated herewith, the repositioning of teeth may be accomplished with the use of a series of removable elastic positioning appliances such as the Invisalign® system available from Align Technology, Inc., the assignee of the present disclosure. Such appliances have a thin shell of elastic material that generally conforms to a patient's teeth but is slightly out of alignment with an initial or immediately prior tooth configuration. Placement of the elastic positioner over the teeth applies controlled forces in specific locations to gradually move the teeth into the new configuration. Repetition of this process with successive appliances including new configurations eventually moves the teeth through a series of intermediate configurations or alignment patterns to a final desired configuration. A full description of an exemplary elastic polymeric positioning appliance is described in U.S. Pat. No. 5,975,893, and in published PCT application WO 98/58596, the content of these documents are incorporated by reference for all purposes.
The appliance is effective in repositioning teeth when it is placed over the patient's teeth. In some implementations, it is desirable to wear these appliances most of the day (e.g., all of the time except when eating and maintaining oral hygiene, such as by brushing or flossing). Although easy and convenient to wear, the patient may not wear the appliance as prescribed by the treatment professional. Extended removal of the appliance, for any reason beyond what is recommended, interrupts the treatment plan and lengthens the overall period of treatment. Since the appliance is removable by the patient, the treatment professional has to rely on the patient to comply with the prescription.
Additionally, there may be many variables and differences in each patient's oral environment and, therefore, one type of compliance indicator may not likely be enough to last for a desired period of wear in every person. Some examples of the factors that may change the wear rate include an amount of saliva produced, one or more tooth anatomies or locations, a composition of saliva, an analysis of sleep habits of a patient, an amount of liquid consumption, and one or more types of liquid consumed, among other criteria. These factors can make the analysis of compliance based upon a wear indicator difficult due to the different wear rates that different people may have.